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A powerful approach to alkoxy radical-mediated remote C(sp^3)–H bonds functionalization

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Science China Chemistry 2018年第5期61卷 505-506页

作者： Cong xiao Wen-jing xiao Department of Chemistry Georgia State University CCNU-u Ottawa Joint Research Centre Key Laboratory of Pesticide & Chemical Biology Ministry of Education College of ChemistryCentral China Normal University

The activation of inert C（sp^3）–H bonds with control of reactivity and selectivity is one of the central topics in chemical sciences.

关键词： A powerful approach to alkoxy radical-mediated remote C H bonds functionalization

Classification-based self-adaptive differential evolution and its application in multi-lateral multi-issue negotiation

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Frontiers of Computer Science 2012年第4期6卷 442-461页

作者： xiaojun BI jing xiao School of Information and Communication Engineering Harbin Engineering UniversityHarbin 150001China School of Information Engineering Liaoning Provincial College of CommunicationsShenyang 110122China

Multi-lateral multi-issue negotiations are the most complex realistic negotiation problems. Automated ap- proaches have proven particularly promising for complex ne- gotiations and previous research indicates evolutionary com- putation could be useful for such complex systems. To im- prove the efficiency of realistic multi-lateral multi-issue ne- gotiations and avoid the requirement of complete informa- tion about negotiators, a novel negotiation model based on art improved evolutionary algorithm p-ADE is proposed. The new model includes a new multi-agent negotiation protocol and strategy which utilize p-ADE to improve the negotia- tion efficiency by generating more acceptable solutions with stronger suitability for all the participants. Where p-ADE is improved based on the well-known differential evolution （DE）, in which a new classification-based mutation strategy DE/rand-to-best/pbest as well as a dynamic self-adaptive pa- rameter setting strategy are proposed. Experimental results confirm the superiority of p-ADE over several state-of-the-art evolutionary optimizers. In addition, the p-ADE based multi- agent negotiation model shows good performance in solving realistic multi-lateral multi-issue negotiations.

关键词： differential evolution global optimum e-commerce agent multi-lateral multi-issue negotiation

Flows Associated to Cameron-martin Type Vector Fields on Path Spaces Over a Riemannian Manifold

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Acta Mathematicae Applicatae Sinica 2013年第3期29卷 499-508页

作者： jing-xiao ZHANG Center for Applied Statistics School of StatisticsRenmin University of China

The flow on the Wiener space associated to a tangent process constructed by Cipriano and Cruzeiro, as well as by Gong and Zhang does not allow to recover Driver’s Cameron-Martin theorem on Riemannian path space. The purpose of this work is to refine the method of the modified Picard iteration used in the previous work by Gong and Zhang and to try to recapture and extend the result of Driver. In this paper, we establish the existence and uniqueness of a flow associated to a Cameron-Martin type vector field on the path space over a Riemannian manifold.

关键词： flow Cameron-Martin type vector field path space Riemannian manifold

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采用小波变换的空间外差干涉图误差分析方法

光谱学与光谱分析 2025年第1期45卷 8-14页

作者：王方原李晓静叶松李树王新强桂林电子科技大学光电工程学院广西桂林541004 广西光电信息处理重点实验室广西桂林541004

空间外差光谱技术(SHS)是一种应用于微弱物质探测、行星勘探以及大气遥感等领域的超光谱分析技术。受实验环境复杂及被测目标信号微弱等因素的影响,空间外差光谱仪的测量结果易出现干涉条纹倾斜、干涉图有斑点噪声等情况,从而最终影响... 详细信息

空间外差光谱技术(SHS)是一种应用于微弱物质探测、行星勘探以及大气遥感等领域的超光谱分析技术。受实验环境复杂及被测目标信号微弱等因素的影响,空间外差光谱仪的测量结果易出现干涉条纹倾斜、干涉图有斑点噪声等情况,从而最终影响测量光谱的精度。为了尝试解决这些问题,提出了基于小波变换的干涉图误差分析方法,对干涉图的斑点噪声水平和条纹倾斜误差进行有效的评价,从而为后续误差校正提供理论基础。首先对无误差的钾灯仿真干涉图加入不同标准差的高斯噪声,利用小波分解提取复小波系数,采用三种噪声估计法对干涉图数据进行计算,结果表明空域相关小波变换法噪声估计结果与真实值偏差最小,而Donoho估计法在修正截距后与真实值具有更好的吻合度。随后采用Db2小波对噪声水平不同的仿真钾灯干涉图进行一层小波分解并提取水平、对角及垂直三个方向的细节系数,采用Donoho估计法对干涉图进行二维噪声分析,有效表征了三幅干涉图各方向上的噪声水平特征。最后对仿真连续光干涉图进行小波分解并提取系数分析,研究了干涉条纹倾斜角度与小波分解系数的关系。研究结果表明,三个方向的小波细节系数估值变化分别在分解到不同层数时具有相似的变化规律:小波细节系数估值与条纹倾斜方向和小波细节系数的所属方向的夹角成反比,条纹倾斜方向与该小波细节系数的方向夹角越小,估值越大,反之则越小,且水平方向分解到第一层、对角方向分解到第二层、垂直方向分解到第三层符合变化规律。该研究是利用小波分解进行空间外差光谱误差分析的有益尝试,也为后续干涉图条纹倾斜误差的校正提供了一种新途径。

关键词：空间外差光谱技术噪声标准差估计干涉图小波变换

Electric-Field Switching of Exciton Spin Splitting in Asymmetrical Coupled Quantum Dots

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Chinese Physics Letters 2012年第8期29卷 202-204页

作者： LI xiao-jing College of Physics and Energy Fujian Normal UniversityFuzhou 350007

The spin splitting of the exciton states in semiconductor asymmetrical coupled quantum dots(CQDs)containing a single magnetic ion is theoretically *** is found that the spin splitting is not the largest when the electric field is *** electric field stronger than that in symmetrical CQDs is necessary to switch the splitting on/*** mixing between the bonding and antibonding hole states consequently results in the bright-to-dark transition of the ground exciton in the photoluminescence spectrum.

关键词： splitting bonding mixing

Preface:special topic on organic photochemistry

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Science China Chemistry 2016年第2期59卷 159-160页

作者： Wen-jing xiao CCNU-u Ottawa Joint Research Center College of Chemistry Central China Normal University

Catalysis under irradiation by visible light has become a highly dynamic and promising research area in chemical sciences. Such catalysis primarily entails photoinduced electron- and energy-transfer chemistry sensitized by polypyridyl complexes, organic dyes, and heterogeneous catalysts. Remarkably though, while the electrochemical and photophysical properties of these catalysts have been extensively studied, only recently has the chemical commu- nity begun to appreciate the great potential of the utilization of visible-light photocatalysis as a broadly useful method- ology to advanced organic synthesis. Since 2008, visible- light photocatalysis has witnessed a rapid development as a possible alternative to strong oxidizing and reducing agents and radical-initiating reagents. Due to the relative obscurity of photoredox catalysis in organic synthesis, the primary focus of this thematic issue will be centered on modem photocatalysis, especially in the context of photo-driven electron- and energy-transfer catalysis.

关键词：有机光化学非均相催化剂光催化氧化专题多吡啶配合物自由基引发剂催化作用能量转移

Topology-assisted deterministic packet marking for IP traceback

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The Journal of China Universities of Posts and Telecommunications 2010年第2期17卷 116-121页

作者： WANG xiao-jing WANG xiao-yin Laboratory of Computer Network Defense Technology Beijing Institute of Technology Beijing 100081 China Xi'an Politics Institute Xi'an 710068 China

A novel deterministic packet marking （DPM） for IP traceback against denial of service （DOS） and distributed denial of service （DDoS） attacks is presented, which features good scalability and high accuracy. In this scheme, an ingress router pre-calculates a Hash of its IP address and splits the Hash into several fragments. When marking a packet, the router randomly selects a fragment to mark into the packet. In the traceback stage the victim identifies the marked router with the help of the map of its upstream routers. Based on the map, the victim can identify a candidate ingress router after receiving only several marked packets. The scheme overcomes defects in previous deterministic packet marking schemes, where too much packets are required to recover a router and high false positive rate occurs in case of large-scale DDoS. Theoretical analysis, the pseudo code and experimental results are provided. The scheme is proved to be accurate and efficient and can handle large-scale DDoS attacks.

关键词： network security DDoS 1P traceback deterministic packet marking (DPM)

Distributed and Consensus Optimization for Non-smooth Image Reconstruction

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Journal of the Operations Research Society of China 2015年第2期3卷 117-138页

作者： xiao-jing Ye Department of Mathematics and Statistics Georgia State UniversityAtlantaGA 30303USA

We present a primal-dual algorithm with consensus constraints that can effectively handle large-scale and complex data in a variety of non-smooth image reconstruction *** particular,we focus on the case that the data fidelity term can be decomposed into multiple relatively simple functions and deployed to parallel computing units to cooperatively solve for a consensual solution of the original *** this case,the subproblems usually have closed form solution or can be solved efficiently at local computing units,and hence the per-iteration computation complexity is very low.A comprehensive convergence analysis of the algorithm,including convergence rate,is established.

关键词： Distributed optimization Parallel computing Consensus Total variation Image reconstruction

A mathematical model capable of describing the liquid flow mainly in a blast furnace

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International Journal of Minerals,Metallurgy and Materials 2009年第5期16卷 505-511页

作者： Cheng-shan Wang xiao-jing Mu College of Materials Science and Engineering Chongqing University Chongqing 400045 China College of Chemistry and Chemical Engineering Chongqing University Chongqing 400045 China

The molten liquid flow inside a packed bed is a familiar momentum transportation phenomenon in a blast furnace. With regard to the reported mathematical models describing the liquid flow within a packed bed, there are some obstacles for their application in engineering design, or some limitations in the model itself. To overcome these problems, the forces from the packed bed to the liquid flow were divided into appropriate body and surface forces on the basis of three assumptions. Consequently, a new mathematical model was built to present the liquid flow inside the coke bed in a blast furnace. The mathematical model can predict the distribution of liquid flowrate and the liquid flowing range inside the packed bed at any time. The predicted results of this model accord well with the experimental data. The model will be applied considerably better in the simulation on the ironmaking process compared with the existent models.

关键词： ironmaking process blast furnace packed bed discrete flow mathematical model